compiler/rustc_passes/src/hir_id_validator.rs

   1 use rustc_data_structures::fx::FxHashSet;
   2 use rustc_data_structures::sync::Lock;
   3 use rustc_hir as hir;
   4 use rustc_hir::def_id::{LocalDefId, CRATE_DEF_ID};
   5 use rustc_hir::intravisit;
   6 use rustc_hir::{HirId, ItemLocalId};
   7 use rustc_middle::hir::map::Map;
   8 use rustc_middle::hir::nested_filter;
   9 use rustc_middle::ty::TyCtxt;
  10
  11 pub fn check_crate(tcx: TyCtxt<'_>) {
  12     tcx.dep_graph.assert_ignored();
  13
  14     if tcx.sess.opts.debugging_opts.hir_stats {
  15         crate::hir_stats::print_hir_stats(tcx);
  16     }
  17
  18     let errors = Lock::new(Vec::new());
  19     let hir_map = tcx.hir();
  20
  21     hir_map.par_for_each_module(|module_id| {
  22         let mut v = HirIdValidator {
  23             hir_map,
  24             owner: None,
  25             hir_ids_seen: Default::default(),
  26             errors: &errors,
  27         };
  28
  29         tcx.hir().deep_visit_item_likes_in_module(module_id, &mut v);
  30     });
  31
  32     let errors = errors.into_inner();
  33
  34     if !errors.is_empty() {
  35         let message = errors.iter().fold(String::new(), |s1, s2| s1 + "\n" + s2);
  36         tcx.sess.delay_span_bug(rustc_span::DUMMY_SP, &message);
  37     }
  38 }
  39
  40 struct HirIdValidator<'a, 'hir> {
  41     hir_map: Map<'hir>,
  42     owner: Option<LocalDefId>,
  43     hir_ids_seen: FxHashSet<ItemLocalId>,
  44     errors: &'a Lock<Vec<String>>,
  45 }
  46
  47 impl<'a, 'hir> HirIdValidator<'a, 'hir> {
  48     fn new_visitor(&self, hir_map: Map<'hir>) -> HirIdValidator<'a, 'hir> {
  49         HirIdValidator {
  50             hir_map,
  51             owner: None,
  52             hir_ids_seen: Default::default(),
  53             errors: self.errors,
  54         }
  55     }
  56
  57     #[cold]
  58     #[inline(never)]
  59     fn error(&self, f: impl FnOnce() -> String) {
  60         self.errors.lock().push(f());
  61     }
  62
  63     fn check<F: FnOnce(&mut HirIdValidator<'a, 'hir>)>(&mut self, owner: LocalDefId, walk: F) {
  64         assert!(self.owner.is_none());
  65         self.owner = Some(owner);
  66         walk(self);
  67
  68         if owner == CRATE_DEF_ID {
  69             return;
  70         }
  71
  72         // There's always at least one entry for the owning item itself
  73         let max = self
  74             .hir_ids_seen
  75             .iter()
  76             .map(|local_id| local_id.as_usize())
  77             .max()
  78             .expect("owning item has no entry");
  79
  80         if max != self.hir_ids_seen.len() - 1 {
  81             // Collect the missing ItemLocalIds
  82             let missing: Vec<_> = (0..=max as u32)
  83                 .filter(|&i| !self.hir_ids_seen.contains(&ItemLocalId::from_u32(i)))
  84                 .collect();
  85
  86             // Try to map those to something more useful
  87             let mut missing_items = Vec::with_capacity(missing.len());
  88
  89             for local_id in missing {
  90                 let hir_id = HirId { owner, local_id: ItemLocalId::from_u32(local_id) };
  91
  92                 trace!("missing hir id {:#?}", hir_id);
  93
  94                 missing_items.push(format!(
  95                     "[local_id: {}, owner: {}]",
  96                     local_id,
  97                     self.hir_map.def_path(owner).to_string_no_crate_verbose()
  98                 ));
  99             }
 100             self.error(|| {
 101                 format!(
 102                     "ItemLocalIds not assigned densely in {}. \
 103                 Max ItemLocalId = {}, missing IDs = {:?}; seens IDs = {:?}",
 104                     self.hir_map.def_path(owner).to_string_no_crate_verbose(),
 105                     max,
 106                     missing_items,
 107                     self.hir_ids_seen
 108                         .iter()
 109                         .map(|&local_id| HirId { owner, local_id })
 110                         .map(|h| format!("({:?} {})", h, self.hir_map.node_to_string(h)))
 111                         .collect::<Vec<_>>()
 112                 )
 113             });
 114         }
 115     }
 116 }
 117
 118 impl<'a, 'hir> intravisit::Visitor<'hir> for HirIdValidator<'a, 'hir> {
 119     type NestedFilter = nested_filter::OnlyBodies;
 120
 121     fn nested_visit_map(&mut self) -> Self::Map {
 122         self.hir_map
 123     }
 124
 125     fn visit_item(&mut self, i: &'hir hir::Item<'hir>) {
 126         let mut inner_visitor = self.new_visitor(self.hir_map);
 127         inner_visitor.check(i.def_id, |this| intravisit::walk_item(this, i));
 128     }
 129
 130     fn visit_id(&mut self, hir_id: HirId) {
 131         let owner = self.owner.expect("no owner");
 132
 133         if owner != hir_id.owner {
 134             self.error(|| {
 135                 format!(
 136                     "HirIdValidator: The recorded owner of {} is {} instead of {}",
 137                     self.hir_map.node_to_string(hir_id),
 138                     self.hir_map.def_path(hir_id.owner).to_string_no_crate_verbose(),
 139                     self.hir_map.def_path(owner).to_string_no_crate_verbose()
 140                 )
 141             });
 142         }
 143
 144         self.hir_ids_seen.insert(hir_id.local_id);
 145     }
 146
 147     fn visit_foreign_item(&mut self, i: &'hir hir::ForeignItem<'hir>) {
 148         let mut inner_visitor = self.new_visitor(self.hir_map);
 149         inner_visitor.check(i.def_id, |this| intravisit::walk_foreign_item(this, i));
 150     }
 151
 152     fn visit_trait_item(&mut self, i: &'hir hir::TraitItem<'hir>) {
 153         let mut inner_visitor = self.new_visitor(self.hir_map);
 154         inner_visitor.check(i.def_id, |this| intravisit::walk_trait_item(this, i));
 155     }
 156
 157     fn visit_impl_item(&mut self, i: &'hir hir::ImplItem<'hir>) {
 158         let mut inner_visitor = self.new_visitor(self.hir_map);
 159         inner_visitor.check(i.def_id, |this| intravisit::walk_impl_item(this, i));
 160     }
 161 }